JPS6031513A - Vinyl chloride graft copolymer resin - Google Patents

Abstract

PURPOSE:The titled copolymer resin having excellent transparency and heat stability and a high softening temperature, obtained by graft-copolymerizing vinyl chloride and another copolymerizable monomer with an alpha-methylstyrene resin. CONSTITUTION:50.0-99.5pts.wt. vinyl chloride and 0-20pts.wt. another vinyl monomer copolymerizable therewith (e.g., ethylene) are graft-copolymerized with 0.5-30pts.wt. alpha-methylstyrene resin having an alpha-methylstyrene content >=50wt% in an aqueous medium in the presence of a suspension stabilizer such as hydroxypropylmethylcellulose. EFFECT:It is possible to obtain a vinyl chloride graft copolymer resin excellent in heat stability, melt flow, Clash-Berg softening temperature. USE:A material for electrostatic capacity type of recording media.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vinyl chloride resin with improved physical properties. Although it is a useful general-purpose resin with physical and physical properties, it has drawbacks such as poor moldability, particularly poor fluidity of the molten polymer, and poor softening temperature. In order to improve moldability, a method of copolymerizing vinyl compounds such as vinyl acetate and alkyl vinyl ether is generally used. However, although copolymerization of such vinyl compounds reduces the viscosity of the molten polymer and improves its fluidity,
On the other hand, other mechanical and physical properties such as thermal stability, tensile strength, and softening temperature are reduced, so that the obtained vinyl chloride copolymers can only be used in very limited applications.

Other methods include graft copolymerizing vinyl chloride onto a copolymer of ethylene and vinyl acetate (hereinafter abbreviated as EVA), acrylic rubber, or the like. Although the graft copolymer obtained by this method has almost no decrease in thermal stability, tensile strength, or softening temperature, it has the disadvantage of a marked decrease in transparency.

The present inventors have determined that thermal stability, without compromising transparency,
As a result of intensive studies to obtain a graft copolymer with excellent flexibility temperature, we found that if vinyl chloride is graft copolymerized to a resin containing 50% by weight or more of α-methylstyrene, transparency, thermal stability, flexibility temperature, etc. Excellent graft P V c
The present invention was completed based on the discovery that the following can be obtained.

That is, in the present invention, 50.0 to 30 parts by weight of vinyl chloride is added to 0.5 to 30 parts by weight of a resin containing 50% by weight or more of α-methylstyrene.
This is a vinyl chloride graft copolymer resin characterized by graft copolymerizing 99.5 parts by weight of vinyl chloride and 0 to 20 parts by weight of another monomer copolymerizable with vinyl chloride.

The resin containing 500 parts by weight or more of α-methylstyrene is
If the amount used is less than ()5 parts JJl, the excellent effects of the present invention cannot be sufficiently obtained, and if it is used in excess of 30%, the melt fluidity will deteriorate, which is not preferable.

The α-methylstyrene resin used in the present invention only needs to contain α-methylstyrene in an amount of 50% by weight or more. Examples of vinyl compounds used together with α-methylstyrene include ethylene, propylene, 1-methylstyrene, etc. α-olefins having 2 to 30 carbon atoms such as butene, styrenes, vinyl esters such as vinyl acetate and vinyl propionate,
Alkyl vinyl ethers having 1 to 28 carbon atoms such as methyl vinyl ether and ethyl vinyl ether, unsaturated fatty acids such as acrylic acid, methacrylic acid, fumaric acid, and maleic acid, and their esters, acrylonitrile,
Examples include unsaturated nitriles such as methacrylnitrile, vinyl chloride, vinylidene chloride, fluorine-containing ethylene, butadiene, isoprene, etc., and these may be used alone or in combination of two or more. This is not preferred because the melt fluidity of the graft copolymer resin obtained by using an α-methylstyrene resin containing 500 parts by weight of a vinyl compound other than α-methylstyrene deteriorates, resulting in poor processability. Note that the degree of polymerization of the α-methylstyrene resin is not particularly limited.

As a vinyl compound used with vinyl chloride, for example, ethylene, propylene, ■-butene, etc. having 2 or more carbon atoms;
30 α-olefins, styrenes, vinyl acetate,
Novinyl esters such as vinyl propionate, methyl vinyl ether, ethyl vinyl ether, etc. with 1 or more carbon atoms
28 alkyl vinyl ethers, unsaturated fatty acids such as acrylic acid, methacrylic acid, fumaric acid, maleic acid and their esters, unsaturated nitriles such as acrylonitrile and methacrylonitrile, vinylidene chloride, fluorine-containing ethylene, butadiene , Inogren, etc., and these may be used alone or in combination of two or more. It is desirable that these vinyl compounds be contained in an amount of 20 parts by weight or less in PVO (graph) to avoid deterioration of physical properties.

PVC graft copolymers can be obtained by various methods such as emulsion polymerization, suspension polymerization, solution polymerization, and bulk type methods.

.

The graph shows how to obtain PVO using a general suspension polymerization method.

Pure water, a suspension stabilizer such as hydroxyglobil methylcellulose, and an α-methylstyrene resin are placed in a jacketed polymerization reactor and suspended. Air inside the can is then removed, and then vinyl chloride alone or A monomer copolymerizable with vinyl chloride is injected.

Thereafter, the inside of the can is heated to a temperature of 100 m from the jacket to dissolve, swell, and disperse the α-methylstyrene resin in the monomer such as vinyl chloride. Thereafter, a radical polymerization initiator is added to initiate graft copolymerization. Since kraft copolymerization is an exothermic reaction, the internal temperature is controlled by a jacket as necessary. After the reaction is completed, unreacted vinyl chloride monomer is removed from the can to obtain a slurry of graft 1) VC. The slurry was dehydrated and dried according to the conventional method (graph)
PVO is isolated.

Also, the charging method to the polymerization reactor is not limited,
Of the charged raw materials such as pure water, turbidity stabilizer, α-methylstyrene resin, and vinyl chloride, α-methylstyrene resin is dissolved or swollen and dispersed in vinyl chloride, and then charged together with vinyl chloride. This method can also be adopted.

Graph obtained with the present invention!・+】 Add compounding agents such as plasticizers, stabilizers, lubricants, cutting impact agents, fillers, ultraviolet absorbers, leveling agents, surfactants, colorants, pigments, etc. to v c as necessary, The mixture is mixed using a known device such as a Henschel mixer or a ribbon blender, and then molded by a known method such as melt extrusion, stamping, injection, etc., and put into practical use.

Graph of the present invention) l) VC has excellent thermal stability and transparency, and has a high softening temperature, so it can be suitably used in the field of hard processing.

The present invention will be explained below with reference to Examples.

Examples-1 to -6, Comparative Example-1 In an autoclave with an internal volume of 3,000 J3, pure water 1.2
00 kg, 60 kg of α-methylstyrene resin with the composition shown in Table 1, and hydroxyglobil methyl cellulose 1.2 K9 were charged, and after replacing the internal air with nitrogen, 540 kg of vinyl chloride was charged. The mixture was stirred at 63° C. for 3 hours to dissolve the α-methylstyrene resin. After that, 3.0 kg of α・α′-azobisisoputyronitrile
, 1.0 kg of 2-mercat ethanol was charged, and 6
Approximately 52°Kg of white powder was obtained at 3°C. U analysis of this product revealed that it contained about 12% of components other than vinyl chloride. The average degree of polymerization was about 490 in all cases.

20 parts by weight of a tin-based stabilizer 1 Adbastab 17MJ” (trademark) to parts by weight of this graft copolymerization pvaioo,
Mix 0.5 parts by weight of stearic acid uniformly, and add 150 parts by weight of stearic acid.
A sheet was prepared by hot roll kneading at 180°C for 10 minutes and pressing at 180°C for 5 minutes. Thermal stability, flow tester flow temperature, crush bar flexibility temperature, and transparency (hereinafter collectively referred to as physical properties) were measured for samples taken from this sheet.

The results are shown in Table 1.

Comparative Example-2 Pure water 1.
200Kg, hydroxyglobil methylcellulose 1.
21<g, α・α′-azobisisobutyronitrile 3
0 Kg, and 2-mercagutoethanol 1.0 Kg
After replacing the air inside with nitrogen, vinyl chloride 6Q OK9 was charged, and the polymerization reaction was continued at 63°C for 18 hours.

Then remove the vinyl chloride and remove the contents? "515 kg of white powder was obtained by over-drying. The average degree of polymerization of this product was 490. Sheet production was carried out in the same manner as in Example-1, and the physical properties were measured.

The results are shown in Table 1.

Comparative Example-3 P V 0 with an average degree of polymerization of 490 obtained in Comparative Example-2
To 100 parts by weight and 14 parts of the α-methylstyrene resin used in Example 6, 20 parts by weight of the tin-based stabilizer "Advustab 17MJ" (trademark) and 0.5 parts by weight of stearic acid per 100 parts by weight of the total resin. The mixture was uniformly mixed, further kneaded for 10 minutes with a hot roll at 150°C, and then pressed for 5 minutes with a hot press at 180°C to form a sheet. Measurement of physical properties is in Example 1
I did the same thing.

The results are shown in Table 1.

Example-7 Example-6 except that vinyl chloride in Example-6 was changed to vinyl chloride 510 9 and propylene 30Kj7
Polymerization was carried out in the same manner as above to obtain white powder stsKg.

Hereinafter, the physical properties were measured in the same manner as in Example-1. The results are shown in Table 2.

Comparative Example-4 In Comparative Example-2, vinyl chloride was replaced with vinyl chloride 56o
Comparative example-2 except that Kg and propylene were changed from 30 to 9
Polymerization was carried out in the same manner as above to obtain 520 kg of white powder.

100 parts by weight of this resin and α-methylstyrene resin (α
- 65% by weight of methylstyrene), 25% by weight of acrylonitrile
To 17 parts by weight (7% by weight of styrene, 3% by weight of methyl methacrylate), 100 parts by weight of a resin compound, 20 parts by weight of the cis-based stabilizer "Advustab 17MJ" (trademark) and 0.5 parts by weight of stearic acid. Mix evenly and add 15
The mixture was kneaded for 10 minutes using hot rolls at 0°C, and then pressed for 5 minutes using a hot press at 180°C to form a sheet. The physical properties were measured in the same manner as in Example 1.

The results are shown in Table 2.

Table 2 Note) Amounts of components other than vinyl chloride determined from the quaternary analysis values of graft Pvc Examples-8 and -9 Graft copolymerizations obtained in Examples-1 and -7 1) V 01
00 parts by weight and 1 piece of conductive carbon Black EC
(Trademark) 20 parts of Il, 1 part of tin stabilizer, 1 part of Adbastab
2.0 parts by weight of 7MJ'' (trademark) and 0.5 parts by weight of stearic acid were uniformly mixed, further kneaded with hot rolls at 140°C for 10 minutes, and pressed at 180°C for 5 minutes to produce a sheet. Thermal stability, flow tester flow temperature, and Krasosberg softness temperature were measured for samples taken from this sheet.

The results are shown in Table 3.

Comparative Example 5 A sheet was prepared using the graft copolymer 11 VO obtained in Comparative Example 2 in the same manner as in Example 8, and its physical properties were measured.

The results are shown in Table 3.

The composition of the present invention has excellent thermal stability, melt flowability, and Krasosberg softness temperature, and can be suitably used as a material for capacitive recording media.

patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. α containing 50% by weight or more of α-methylstyrene
- Characterized by graft copolymerization of 50.0 to 99.5 parts by weight of vinyl chloride and 0 to 20 parts by weight of a vinyl compound copolymerizable with vinyl chloride to 0.5 to 30 parts by weight of methylstyrene resin. Vinyl chloride graft copolymer resin with improved thermal stability and high flexibility temperature.